1. Field of the Invention
This invention relates to a scroll type compressor, and more particularly, to a lubricating mechanism for a hermetically sealed scroll type compressor.
2. Description of the Prior Art
A hermetically sealed scroll type compressor is disclosed in Japanese Patent Application Publication No. 61-87994 and is shown in FIG. 1. A hermetically sealed housing includes inner chamber 1 which is maintained at discharge pressure. However, the compression mechanism including interfitting scrolls 2 and 3 and the forward end of the drive mechanism are isolated from inner chamber 1 behind partition 4. Channel 5 links intermediate pocket 6 of the interfitting scrolls with chamber 7. Refrigerant gas flows through inlet port 8 and is compressed inwardly by the scrolls towards central pocket 9, and flows to discharge chamber 12 through hole 10 and eventually outlet port 11 to an external element of the refrigeration system. Some of the refrigerant gas also flows to inner chamber 1.
The intermediate pressure in pocket 6 is maintained in chamber 7 which contains the forward end of the drive mechanism including bearings 14-16. When the compressor operates, lubricating oil mixed with the refrigerant gas, which settles at the bottom of inner chamber 1, flows through channel 13 to lubricate bearings 14-16 of the drive mechanism due to the pressure difference between inner chamber 1, which is maintained at the discharge pressure, and the intermediate pressure.
However, it is difficult to utilize the above type of lubricating mechanism in a hermetically sealed scroll type compressor in which the inner chamber is maintained at the suction pressure. Since the suction pressure is lower than the discharge pressure and the intermediate pressure, the lubricating fluid will not flow to the drive mechanism in this type of compressor.